The present invention relates to a waterproof connector which is designed to be waterproof in the inside thereof by a sealing member such as a packing inserted therein, and a method of manufacturing the same.
As a conventional waterproof connector, there has been disclosed, for example, in Japanese Patent Laid-Open No. 61(1986)-179077, which is shown in FIGS. 1 and 2. FIG. 1 is an exploded perspective view showing a waterproof connector 1 and a connector 2, which constitutes a mating pair. In this mating pair, the waterproof connector 1 is one mate and the connector 2 is the other mate. As shown in FIG. 2, the waterproof connector 1 comprises an inner housing 5 positioned in an outer housing 3 with a predetermined space S therebetween. The inner housing 5 accommodates a connection terminal 4a of one wire 4. A packing 6 made of rubber is inserted between the outer housing 3 and the inner housing 5.
On the other hand, as shown in FIG. 1, the connector 2 of the other mate comprises a housing 7 which is allowed to be entered in the predetermined space S, and the housing 7 accommodates a connection terminal 8a of the other wire 8 in its rear end portion. The connection terminal 8a and the connection terminals 4a are designed so that they are engaged with the housing 7 and the inner housing 5 by spacers 9 and 9a, respectively.
The housing 7 of the connector 2 of the other mate is allowed to be entered in the predetermined space S of the waterproof connector 1, whereby the connection terminal 4a of one mate and the connection terminal 8a of the other mate contact with each other. Then, the packing 6 is pressed toward a bottom wall 3a of the outer housing 3 by a step portion (not shown) formed inside the tip end of the housing 7. Thus, the packing 6 swells in its thickness direction by being compressed between the bottom wall 3a and the step portion, and a space between an outer circumference of the inner housing 5 and an inner circumference of the housing 7 is sealed liquid-tightly.
However, in the conventional waterproof connector 1, a waterproof function by use of the packing 6 is not exerted until the packing 6 swells in its thickness direction by entering the connector 2 of the other mate in the waterproof connector 1. In a state where the connector 2 of the other mate is not inserted in the waterproof connector 1, the packing 6 should be inserted in the outer circumference of the inner housing 5 softly without allowing the packing 6 to be compressively contacted thereto, from viewpoints of durability of the packing 6.
Therefore, in the case where an enter port 1a of the waterproof connector 1 is connected to the connector 2 of the other mate so as to be directed downward, the packing 6 may easily fall from the enter port 1a. When the packing 6 falls, a connection operation needs to be performed after inserting the packing 6 again. Also in such a case, a device is required, in which a connection operation is performed while closing the enter port 1a with fingers so that the packing 6 does not fall again. Therefore, much time is required for assembling the waterproof connector 1, thus deteriorating operationality.
Accordingly, the present invention was made to solve the conventional problems, and an object of the present invention is to provide a waterproof connector capable of surely preventing a sealing member from coming away from an outer housing without increasing cost significantly, by fixing the sealing member to the outer housing with simple means, the sealing member being inserted for waterproof. The object of the present invention is also to provide a method of manufacturing the waterproof connector.
The waterproof connector of the present invention as defined in claim 1 comprises an inner housing accommodating a connection terminal; an outer housing surrounding the inner housing inserted in an insertion port with a predetermined space portion therebetween and having the insertion port provided in a block wall and an enter port provided in its tip end; and a sealing member inserted in the space portion, wherein a holding projection extending from the sealing member to the block wall is provided, a through hole inserting the holding projection therein is provided in the block wall, and the holding projection is inserted in the through hole. In such a constitution, thermoplastic resin covers at least an exposed portion of the holding projection, which is exposed from the through hole, from the outside of the block wall.
In this case, the sealing member, which is inserted in the space portion between the outer housing and the inner housing, allows the holding projection, which is provided so as to protrude from the sealing member, to be inserted in the through hole formed in the block wall of the outer housing. At this time, since the exposed portion of the holding projection exposed from the through hole is at least covered with the thermoplastic resin from the outside of the block wall, the exposed portion is fixed to the block wall by the thermoplastic resin. Thus, with a simple structure in which the holding projection is formed in the sealing member, the through hole is formed in the block wall, and the thermoplastic resin is filled by inserting the holding projection in the through hole, the sealing member can be surely fixed to the outer housing.
In the waterproof connector as defined as claim 1, the waterproof connector of the present invention as defined in claim 2 is characterized in that the whole of the protrusion portion is covered with the thermoplastic resin extending from the outside of the block wall of the outer housing to the outside of the protrusion portion of the inner housing.
In this case, by covering the whole protrusion portion of the inner housing from the outside of the block wall of the outer housing to the outside of the protrusion portion of the inner housing with the thermoplastic resin, the portion of the inner housing inserted in the insertion port and the portion accommodating the connection terminal can be fixed by the thermoplastic resin and liquid-tightly sealed.
A manufacturing method of the waterproof connector of the present invention as defined in claim 3 comprises the steps of: inserting an inner housing accommodating a connection terminal from an insertion port provided in a block wall of an outer housing; inserting and squeezing a sealing member in a predetermined space portion provided between an outer housing and the inner housing from an enter port provided in a tip end of the outer housing; inserting a holding projection provided so as to protrude from the sealing member in a through hole provided in the block wall; and covering at least an exposed portion of the holding projection exposed from the through hole with thermoplastic resin from the outside of the block wall.
In this case, since the sealing member can be inserted in the predetermined space portion as a guide space, which is provided between the outer housing and the inner housing, the sealing member can be guided easily and surely to a position facing the block wall by being simply squeezed toward the inside of the space portion in the state where the sealing member is inserted in the space portion. Therefore, the holding projection is easily inserted in the through hole of the block wall by squeezing the sealing member. After the holding projection is inserted in the through hole in such a manner, at least the exposed portion of the holding projection is covered with the thermoplastic resin from the outside of the block wall, whereby the sealing member is easily fixed to the outer housing.